Abstract: In order to solve the problem of magnesium-lithium alloy easy to corrosion and low reliability of protection technology, and truly achieve the engineering application of magnesium-lithium alloy, the new alloy microstructure composition design, surface treatment technology and comprehensive protection aspect were stud ied through the new alloy microstructure composition design. The problem of low key magnesium-lithium alloy strength was sloved,which can make the material corrosion resistance achieve and maintain at a certain level. The new composite surface treatment technology and comprehensive protection technology were used to break through the limitation of the application bottleneck of poor corrosion resistance of magnesium-lithium alloy and realize the real engineering application of magnesium-lithium alloy.